Boolean IOSharedDataQueue::initWithCapacity(UInt32 size)
{
IODataQueueAppendix * appendix;
vm_size_t allocSize;
if (!super::init()) {
return false;
}
_reserved = (ExpansionData *)IOMalloc(sizeof(struct ExpansionData));
if (!_reserved) {
return false;
}
if (size > UINT32_MAX - DATA_QUEUE_MEMORY_HEADER_SIZE - DATA_QUEUE_MEMORY_APPENDIX_SIZE) {
return false;
}
allocSize = round_page(size + DATA_QUEUE_MEMORY_HEADER_SIZE + DATA_QUEUE_MEMORY_APPENDIX_SIZE);
if (allocSize < size) {
return false;
}
dataQueue = (IODataQueueMemory *)IOMallocAligned(allocSize, PAGE_SIZE);
if (dataQueue == 0) {
return false;
}
bzero(dataQueue, allocSize);
dataQueue->queueSize = size;
// dataQueue->head = 0;
// dataQueue->tail = 0;
if (!setQueueSize(size)) {
return false;
}
appendix = (IODataQueueAppendix *)((UInt8 *)dataQueue + size + DATA_QUEUE_MEMORY_HEADER_SIZE);
appendix->version = 0;
if (!notifyMsg) {
notifyMsg = IOMalloc(sizeof(mach_msg_header_t));
if (!notifyMsg)
return false;
}
bzero(notifyMsg, sizeof(mach_msg_header_t));
setNotificationPort(MACH_PORT_NULL);
return true;
}
void IOHIDEventQueue::start()
{
if ( _lock )
IOLockLock(_lock);
if ( _state & kHIDQueueStarted )
goto START_END;
if ( _currentEntrySize != _maxEntrySize )
{
mach_port_t port = notifyMsg ? ((mach_msg_header_t *)notifyMsg)->msgh_remote_port : MACH_PORT_NULL;
// Free the existing queue data
if (dataQueue) {
IOFreeAligned(dataQueue, round_page_32(getQueueSize() + DATA_QUEUE_MEMORY_HEADER_SIZE));
dataQueue = NULL;
}
if (_descriptor) {
_descriptor->release();
_descriptor = 0;
}
// init the queue again. This will allocate the appropriate data.
if ( !initWithEntries(_numEntries, _maxEntrySize) ) {
goto START_END;
}
_currentEntrySize = _maxEntrySize;
// RY: since we are initing the queue, we should reset the port as well
if ( port )
setNotificationPort(port);
}
else if ( dataQueue )
{
dataQueue->head = 0;
dataQueue->tail = 0;
}
_state |= kHIDQueueStarted;
START_END:
if ( _lock )
IOLockUnlock(_lock);
}
